Age Calculator
Find out your exact age in years, months, days, total days alive, and how long until your next birthday.
Results update as you change your date of birth. Today's date is taken from your device clock; if it's wrong, the age will reflect that.
Formula
Age is calendar arithmetic between your date of birth and today's date — counted as whole years (you're 30 from your 30th birthday until the day before your 31st), then whole months and days from your last birthday for the precision breakdown. The day-of-week-born is computed from the Gregorian calendar using your DOB. Leap-year birthdays (29 February) celebrate on 28 February in non-leap years.
Related calculators
Frequently asked questions
How is age calculated?▾
Calendar arithmetic from your date of birth to today. Years are counted whole (you're 30 from your 30th birthday until the day before your 31st), then months and days are counted from your most recent birthday for the precise breakdown.
What's the day-of-week-born calculation?▾
Computed from the Gregorian calendar using your date of birth. The US has been on the Gregorian calendar since adoption (which Britain and its colonies switched to in 1752), so the calculation works for any US-applicable date back to 1752 onwards.
What about 29 February (leap day) birthdays?▾
Leaplings celebrate on 28 February in non-leap years in this calculator. The US has no consistent legal rule about which day a leapling 'turns' a year older — it's typically a personal preference and may matter for legal-age thresholds (drinking, voting, etc.) which most states treat as 1 March.
Why is age important for retirement?▾
Several US milestones tie to specific ages: 59½ for IRA early-withdrawal without penalty, 62 for early Social Security, 65 for Medicare, 67 for full Social Security retirement age (for those born 1960+). This calculator gives you your exact current age; SSA.gov gives you the eligibility schedule.
Can I calculate dog/cat years?▾
Not directly. The 7-human-years-per-1-dog-year rule is a folk myth — a 1-year-old dog is more like 15 in human terms, then ages slow. AVMA publishes a more accurate conversion. This calculator does human-only age.
What if my birthday is today?▾
It'll show 'Next birthday: Today!' Happy birthday!